DID Methods in ACA-Py

Decentralized Identifiers, or DIDs, are URIs that point to documents that describe cryptographic primitives and protocols used in decentralized identity management. DIDs include methods that describe where and how documents can be retrieved. DID methods support specific types of keys and may or may not require the holder to specify the DID itself.

ACA-Py provides a DIDMethods registry holding all the DID methods supported for storage in a wallet

Askar and InMemory are the only wallets supporting this registry.

Registering a DID method

By default, ACA-Py supports did:key and did:sov. Plugins can register DID additional methods to make them available to holders. Here's a snippet adding support for did:web to the registry from a plugin setup method.

WEB = DIDMethod(
    name="web",
    key_types=[ED25519, BLS12381G2],
    rotation=True,
    holder_defined_did=HolderDefinedDid.REQUIRED  # did:web is not derived from key material but from a user-provided respository name
)

async def setup(context: InjectionContext):
    methods = context.inject(DIDMethods)
    methods.register(WEB)

Creating a DID

POST /wallet/did/create can be provided with parameters for any registered DID method. Here's a follow-up to the did:web method example:

{
    "method": "web",
    "options": {
        "did": "did:web:doma.in",
        "key_type": "ed25519"
    }
}

Resolving DIDs

For specifics on how DIDs are resolved in ACA-Py, see: DID Resolution.